When is a scala partial function not a partial function?

While creating a map of String to partial functions I ran into unexpected behavior. When I create a partial function as a map element it works fine. When I allocate to a val it invokes instead. Trying to invoke the check generates an error. Is this expected? Am I doing something dumb? Comment out the

For convenience, Scala lets you omit empty parens when calling a method, but it's clever enough to see that the expected type in the first case is ()=>Unit, so it doesn't remove all the parens for you; instead, it converts the method into a function for you.

In the val check case, however, it looks just like a function call result getting assigned to a variable. In fact, all three of these do the exact same thing:

val check = dream
val check = dream()
val check = dream()()

If you want to turn the method into a function, you place _ after the method in place of the argument list(s). Thus,